#include <bits/stdc++.h>
using namespace std;
#define sz(x) ((int)size(x))
#define all(x) begin(x), end(x)
#define trace(x) cout << #x << ": " << (x) << endl;
typedef long long ll;
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
int rand(int l, int r) { return (int) ((ll) rnd() % (r - l + 1)) + l; }
const int N = 200000, infI = 1e9 + 7;
const ll infL = 3e18;
vector<int> g[N];
ll dp[3][N];//LL???
int depth[N], parent[N], wow[N];
void pull(int v) {
dp[0][v] = 0;
dp[1][v] = dp[2][v] = infL;
if (sz(g[v]) <= 1) {
//v is a leaf
dp[1][v] = 1;
} else {
for (int to: g[v]) {
if (to != parent[v]) {
array<ll, 3> dq = {dp[0][v], dp[1][v], dp[2][v]};
dp[0][v] = min({dq[2] + dp[2][to], dq[1] + dp[1][to]});
dp[1][v] = min({dq[0] + dp[1][to], dq[2] + dp[1][to], dq[1] + dp[2][to]});
dp[2][v] = min({dq[0] + dp[2][to], dq[2] + dp[2][to], dq[1] + dp[1][to]});
}
}
dp[1][v] += 1;
dp[2][v] += 2;
}
}
void dfs(int v, int p) {
if (p != -1) {
depth[v] = depth[p] + 1;
}
parent[v] = p;
dp[0][v] = 0;
dp[1][v] = dp[2][v] = infL;
if (sz(g[v]) <= 1) {
//v is a leaf
dp[1][v] = 1;
} else {
for (int to: g[v]) {
if (to != p) {
dfs(to, v);
array<ll, 3> dq = {dp[0][v], dp[1][v], dp[2][v]};
dp[0][v] = min({dq[2] + dp[2][to], dq[1] + dp[1][to]});
dp[1][v] = min({dq[0] + dp[1][to], dq[2] + dp[1][to], dq[1] + dp[2][to]});
dp[2][v] = min({dq[0] + dp[2][to], dq[2] + dp[2][to], dq[1] + dp[1][to]});
}
}
dp[1][v] += 1;
dp[2][v] += 2;
}
}
void zhfs(int v, int p, int omg = -1) {
if (dp[1][v] >= infL) {
omg = v;
}
wow[v] = omg;
for (int to : g[v]) {
if (to != p) {
zhfs(to, v, omg);
}
}
}
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
int n, q;
cin >> n >> q;
int root = -1;
for (int i = 0; i < n - 1; ++i) {
int a, b;
cin >> a >> b;
--a, --b;
g[a].push_back(b);
g[b].push_back(a);
}
int mxx = 0;
for (int i = 0; i < n; ++i) {
mxx = max(mxx, sz(g[i]));
}
for (int i = 0; i < n; ++i) {
if (sz(g[i]) > 1) {
root = i;
break;
}
}
assert(root != -1);
dfs(root, -1);
// trace(dp[0][root]);
zhfs(root, -1);
while (q--) {
int D;
cin >> D;
vector<int> a(D);
for (int i = 0; i < D; ++i) {
cin >> a[i];
--a[i];
}
assert(D == 1);
if (sz(g[a[0]]) == 1) {
cout << (dp[0][root] >= infL ? -1 : dp[0][root] + 1) << '\n';
} else {
cout << (dp[1][root] >= infL ? -1 : dp[1][root] + depth[a[0]] - (wow[a[0]] == -1 ? 0 : depth[wow[a[0]]] * 2)) << '\n';
}
}
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
7 ms |
10068 KB |
Execution killed with signal 6 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
13 ms |
11092 KB |
Execution killed with signal 6 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
14 ms |
12116 KB |
Execution killed with signal 6 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
16 ms |
14292 KB |
Execution killed with signal 6 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
47 ms |
9684 KB |
Output is correct |
2 |
Runtime error |
40 ms |
18916 KB |
Execution killed with signal 6 |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
89 ms |
12188 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
7 ms |
10068 KB |
Execution killed with signal 6 |
2 |
Halted |
0 ms |
0 KB |
- |